Introduction to System Service and DHCP

Introduction to System Service and DHCP

 Introduction to System Service:-

Every computer that connect to network require some IP address assign permanently to a computer host known as static IP address and some IP address leased by DHCP server for a limited period of time known as dynamic IP address.

There are 2 standard IP address

1. IPv4
2. IPv6

IPv4 has a 32 bit and are in Octet-doted decimal lists

Example: 192.168.254.254

IPv6 address have 120 bits

To check the connectivity

#ping 172.24.254.254

To check the IP address

#ifconfig

To set the IP address

#netconfig

Or

#vi /etc/sysconfig/network

Or

#vi /etc/sysconfig/network-scriptd/ifcfg-eth0

Device = eth0

Boot Proto = static

Onboot = yes

IPaddr = 172.24.0.2

Netmask = 255.255.0.0

Gateway = 172.24.254.254

To make Network UP and DOWN

#ifdown eth0

#ifup eth0

We can also assign temporary IP address to a LAN card. It will remain until we restart the computer then after that it will take IP address from ifcfg-eth0

#ifconfig eth0 172.24.0.10

Introduction To System Service

According to the service management, service are divided into three category

1. service which are managed by init command, which are not TCP/IP services
2. service which are managed by service command
3. service which are based on xinetd that is some back ground process services

to check the service whether ON or OFF use

#service service_name status

#chkconfig –list

#chkconfig –list service_name

Example:

#service nfs status

#chkconfig –list

#chkconfig –list nfs

To Make service ON or OFF

#chkconfig nfs on

#chkconfig nfs off

To stop the particular service for particular Run level

#chkconfig –level 3 nfs off

#chkconfig –level 3 5 on/off

To make on or off in run level 3 and 5

#ntsysv : will start /stop all the services in a particular run level. It will display the dialog box in which all the services are mentioned

 DHCP Dynamic Host Configuration Protocol:

 

DHCP provides IP address to host computer dynamically by the range of addresses or statically or fixed address by MAC address

Service Profile

Type               :           System V managed Service

Package          :           dhcp

Daemon         :           dhcpd

Script              :           dhcpd

File                  :           /etc/dhcpd.conf

Port                 :           67,68

 

First check the rpm

#rpm –q dhcp

Copy and rename dhcpd.conf.sample to dhcpd.conf in /etc

#cp /usr/share/doc/dhcp-3.0.1/dhcpd.conf.sample /etc/dhcpd.conf

Now open file

#vi /etc/dhcpd.conf

Set the following configuration

Subnet             :           172.24.0.0;

Netmask         :           255.255.0.0;

Option router :           172.24.254.254;

Option subnet-mask : 255.255.0.0;

Option nis-domain : “RHCE”;

Option domain-name : “example.com”;

Option domain-name-server : 172.24.254.254;

Range dynamic-bootp 172.24.0.1 172.24.0.10

Save and exit

Start the service

#service dhcpd restart

#service portmap retstart

#chkconfig dhcpd on

#chkconfig portmap on

Client Side

#dhclient

Dhclient is used to give the request to dhcp server to assign an address to client

Now if we want to assign the static IP address by their MAC address

#vi /etv/dhcpd.conf

Set the following configuration

host stationX {

            hardware Ethernet 00:34:e3:5r:q1:34;

fixd-address 172.24.0.54;

where

x : Station number

 Thanks ,